At 2 p.m. Monday, the hour when something was allegedly supposed to happen, church bells chimed across the University of Pennsylvania. Students clustered by College Green looked around: no disturbance.

Fifteen minutes later, tourists posed one by one in front of the Ben Franklin statue at the center of campus. They smiled, smoothed their hair. The absence of news was the news.

Across the region Monday, colleges and universities had stepped up security as students wrestled with whether to go to classes in the face of an unnerving anonymous threat.

The attack did not materialize.

On Friday, the day after Christopher Harper-Mercer, 26, killed eight students and their professor in a classroom at Umpqua Community College in Roseburg, Ore., an anonymous Internet poster had warned of an attack on a "university near Philadelphia."

The warning said the incident would take place at 1 p.m. Central Time, which was 2 p.m. in Philadelphia.

Federal authorities passed along the information to local campus officials, who warned their students to be vigilant.

ATF Special Agent Steve Bartholomew, a spokesman for the federal agency, stressed that "there has been no specific threat identified, aside from the mention of the universities and the date and time."

But after the shooting in Oregon, he said, the threat was enough to warrant advising area schools and local law enforcement on Friday.

Maureen S. Rush, head of Penn's police force, said "it would be inappropriate and unconscionable not to have put out the alert for all of our universities and for all of us to be particularly on guard." Rush called in off-duty officers and extended the shifts of others.

But she said that it also would not have been right to shut down the campus.

"The reality is it's like a bomb threat. You can't cancel class every time," she said. "So you want to keep life as normal as possible unless you have something that's a lot more direct than what we received."

At Drexel, students had to show ID to get into academic buildings. At Temple, officers from the Department of Homeland Security stood along Polett Walk, and a white van from the Philadelphia Sheriff's Office rolled down Norris Street. Philadelphia police were stationed on 12th Street.

The fear seemed on more public display at Penn, where nearly three-quarters of the students responding to an unscientific online poll by the Daily Pennsylvanian said they were afraid to go to classes.

Rush said the department had received more than 100 calls since the alert, most of them from concerned parents. She also said the department received about 15 calls of suspicious activity on Monday. Officers checked out each one and found no problems, she said.

In addition, a Facebook page called "Not Going to Class" went up at Penn, saying: "Not going to class because it is OK to be worried, it is OK to be afraid, and it is OK to value your life and take measures to stay safe after a threat has been made against it. Stay safe everyone, regardless of whether or not you go to class."

Scott Rubenstein, a Penn freshman from Arizona, said: "I'm staying home because it's better to be safe than sorry, but I feel better knowing the university is taking every precaution they can and that the entire community is taking this seriously."

Some professors saved students the trouble of making a choice by canceling their lessons.

For those classes that did take place, students reported lower than usual attendance, even earlier in the day.

"I don't think that canceling classes is the right idea," said Brendan Coppinger, a Drexel University sophomore from Connecticut. "It gives way too much attention to the people who just post random crap like this online. I don't expect anything to happen here."

Zach Fetah, 19, a Drexel student from Chesterfield, said he planned to attend his 2 p.m. Russian course.

"I'm concerned," the sophomore computer science major said, "but on the other hand, I think there's a really good chance it's just some 'edge lord' trying to scare people."

At Villanova, sophomore Claire Lavelle described the mood as "a mixture of outrage and slight fear."

"We're sick over this," the Georgia native said.

Elliot Slade, 20 a student from Britain, called the scene "surreal."

"There's been a lot of hysteria and panic," he said. "The fact that this is a problem is ridiculous . . . The fact that it could happen is even scarier." But, he said, he was still going to class.

An Inquirer reporter interviewing students at Villanova was issued a warning for trespassing by school security and Radnor police and threatened with arrest if he returned.

One Drexel professor, Marilyn Musket, worked the topic of the threat into her Sociology 101 lecture. The subject: What makes a fact a fact and the statistics of probability.

Federal authorities had spotted the threat on 4chan, a sprawling collection of message boards known for hosting some of the Internet's most offensive content and some of its most infamous trolls.

It is the birthplace of the harmless LOLcats meme, but also where the hacker collective Anonymous got its start. It is where last year's massive leak of celebrity nudes was first posted, where users once teamed up to harass the family of a teenage suicide victim, and where posters rail anonymously against "normies" - in other words, anyone not on 4chan.

Several news outlets have reported that federal authorities were investigating a post on 4chan's /r9k/ message board that had seemed to predict the Oregon shooting.

"Some of you guys are alright. Don't go to school tomorrow if you are in the northwest," the post, written Sept. 30, read.

On Friday, another post on /r9k/ warned of the attack at a Philadelphia-area college.

"The Beta Rebellion has begun," the anonymous poster wrote.

"A fellow robot will take up arms against a university near Philadelphia." The poster, for some reason, said the attack would occur at 1 p.m. Central Time.

Philadelphia, Miss., is in that time zone, but there was no indication Monday any precautions were taken at schools near there.

In its current incarnation, 4chan's /r9k/ board is a haven for users who refer to themselves as "betas" - passive, sexually frustrated young men - and share stories of awkward social encounters, frequently in misogynistic tones. In the thread where the original threat was posted on Friday, some users seemed to encourage the poster, writing "DO IT" and "the uprising shall commence!" Others told the poster to prepare for scrutiny from law enforcement.

"Try not to cry when the police interrogate you for this thread," one wrote.

By Monday, /r9k/ users were debating whether the threat was real at all. "How many false threats have there been on 4chan?" one wrote. "There was no reason in the world to think this guy was legit."

After the 2 o'clock hour passed, Kaylee Slusser, 18, a Penn freshman from Wilkes-Barre, sounded a note of relief.

"Got my Starbucks," she said, pointing to the coffee place at 34th and Walnut. "There was a SWAT team in there. So we're good to go."

Staff writers Aubrey Whelan, David Klein and Jack Tomczuk contributed to this article.

ssnyder@phillynews.com

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